Re: Low capped TCP network speeds over the Internet

[David Brownlee <abs%absd.org@localhost>]

On Mon, 9 Mar 2026 at 23:59, Michael van Elst <mlelstv%serpens.de@localhost> wrote:
>
> gdt%lexort.com@localhost (Greg Troxel) writes:
>
> >also being reasonable in memory use for small machines is hard; it needs
> >auto-adjust, not just saying that 5 MB should be allocated for every TCP
> >connection.
>
> The socket buffer size is a limit, not an allocation. Your normal
> connections (in LAN, or with little traffic) still use small
> buffers.

I believe it's further complicated because some of these values
require pre-allocation of VM space, so could be an issue on 32 bit
machines but not 64 bit low memory machines.

In an ideal world NetBSD could autoconfigure to "balanced" (cue much
handwaving) values based on some combination of 32/64 bitness and
available memory, which sounds like an interesting project for someone
:)

In the meantime

- Are there some values which should just be bumped by default?
- Can we get some autoconfiguration in, even a brute force of another
set of defaults if the system has more than (say) 256M?
- Failing (or even in combination with) the above, would it make sense
to have some commented out suggestions in the default sysctl.conf, or
in /usr/share/examples/sysctl.conf?

Thanks

David